If you choose All Contacts, this maybe make your contacts messy. Because the previous Gmail keep all those send / received email to the contacts, and collected a lot of spam email address too.

Export in vCard Format, this will be version 3.0 vCard.

BEGIN:VCARD
VERSION:3.0

I know iOS do not support version lower than that like exporting from old Symbian.

Save the Contacts.vcf to your Documents or Desktop, and you will use it to import later.

Import to iCloud

You can access your iCloud from any browser that have internet connection. This make everything easier. If you do not have iCloud account, you can register one from there.

Login to your iCloud account, with your username and password.

Click on the big Contacts icon

The bottom there have a small gear icon.

Click it and access to Import vCard.

So, choose the Contacts.vcf that you export just now, into your iCloud.

Reason to use this way

I’m using this way, because no need to use Microsoft Outlook or Windows Contact, since the iCloud can sync direct from Outlook only in PC.
Some may ask for
How to transfer contact from Google to iPad ?